Concrete walls are commonly used in all types of building construction throughout the world. Concrete shear walls provide a cost effective means to provide fire protected lateral resistance systems for building structures. To make concrete walls, beams and columns formwork is used to retain poured concrete into its desired shape. Formwork is typically stripped away from the concrete after it sets and the formwork is reused.
In the past concrete walls were formed with planks or plywood fastened to vertical and horizontal spaced structural members that provide a form for the wet concrete. When the concrete is being poured and it is wet, for a typical 10 foot high wall 10″ thick, the pressures at the bottom inside faces of the form can be greater than 350 pounds per square inch. Formwork needs to be robust to take the inherently high pressures and abuse, so that a concrete pour does not experience blow-outs. Typically the two opposing sides or faces of the formwork wall are tied together with metal components such as threaded rods or wires. The ties pass from outside one wall to the outside of the opposite wall, after the ties are passed through the walls and through the vertical or horizontal structural members and fixed to restrain the form walls relative to each other while the concrete is wet. Sometimes the metal ties are left in place after the wall is poured.
While the conventional formwork for concrete walls has worked well for many years, they have some disadvantages. If the space between adjacent buildings is tight, the form work might be left in place after the construction is finished. While structurally this works it is not particularly aesthetically pleasing. As well, erecting the formwork on site can be time consuming and in a busy construction market it can be difficult to get the formwork trades. The availability of the formwork trades can significantly affect the flow of work on the job site.
Accordingly it would be advantageous to provide an alternative to the prior art formwork systems.